The invention relates to electric batteries and to methods of manufacturing the same. The invention is particularly applicable to electric batteries of the type which comprise a plurality of individual dry cells which are located within a casing and electrically connected together to form a battery.
Standard dry cells are well known and commonly comprise cylindrical units having an output voltage of about 1.5 volts. It is also known to assemble a plurality of such cells in a common battery casing with appropriate series or parallel connections between the cells so as to provide a suitable electrical output at battery terminals.
Commonly, the battery is provided with external terminals and the battery casing is provided with internal connections to interconnect the cells with each other and with the external battery terminals. One such arrangement is shown, by way of example, in British Patent Specification No. 1331800.
Problems do however arise in providing suitable internal electrical connections within the battery casing. Previous proposals have involved the use of soldered wire joints or separate spring contacts which have to be fitted individually into position in the battery casing. The batteries have to be capable of withstanding shock and previous proposals have included pouring a suitable blocking material into the casing once the cells have been located in position so as to prevent movement of the battery cells. These previous proposals are inherently labour intensive in their construction and therefore expensive. Furthermore, the use of soldered joints and materials, such as bitumen, to hold the cells in place in the battery, tend to lead to the introduction of dirt during assembly.
It is an object of the present invention to provide improved internal connections within such a battery and an improved method of manufacturing such internal connections.